Field of the Invention
The present disclosure relates to a recording element substrate including memory elements, a liquid discharge head including the recording element substrate, and a recording apparatus which performs recording using the liquid discharge head.
Description of the Related Art
In general semiconductor substrates (recording element substrates), a poly fuse memory is generally used as an one time programmable (OTP) read only memory (ROM) which internally records unique information, such as a product ID or a setting parameter. Poly silicon which forms gate wiring or a resistance element of a transistor is used for the poly fuse memory, and has an advantage in that a memory is formed on a semiconductor substrate without additionally performing an existing semiconductor production process. As a reading/writing principle of the poly fuse memory, poly silicon wiring is fused for disconnection by heat generated due to a flow of current and a change of a resistance value is detected so as to be used as a memory.
The poly fuse memory requires a large control transistor which drives large current in a degree that the poly silicon wiring is fused for disconnection, and has a large area occupied by an element group (hereinafter also referred to as a “memory module”) required for function of 1 bit of a memory. However, the number of memory bits required for a product is generally 32 to 48 bits, and therefore, an occupied area in the semiconductor substrate is approximately 5% or less.
However, in recent years, a large amount of memory (for example, approximately 128 bits or more) is required for higher accuracy control performed by an apparatus in addition to unique information, such as a product ID or a setting parameter. For example, in a case of a recording apparatus, a state of aging effect at a time of use, such as a recording material use amount, is required to be recorded inside a recording head.
Therefore, as a memory which realizes a memory module smaller than that of the poly fuse memory, Japanese Patent Laid-Open No. 2014-58130 discloses an anti-fuse memory (memory element). The anti-fuse memory has an advantage in that the anti-fuse memory may be generated by a general semiconductor production process without additionally performing a special process. The anti-fuse memory is formed by a gate oxide film of an MOS transistor, and an overvoltage is applied to the gate oxide film for short-circuit so that a change of a characteristic of the gate oxide film is used as a memory.
For example, in a case where an anti-fuse memory is used as a memory element, a logic circuit for the memory element which receives a signal transmitted from a signal supply circuit is provided to select a memory in which information is written.
If the number of memory elements mounted on a semiconductor substrate is increased, a region for mounting logic circuits corresponding to the memory elements and wiring for supplying signals to the logic circuits is also increased in addition to a region for mounting the memory elements. Accordingly, an area of the semiconductor substrate may be disadvantageously increased.